There are several container runtime environments available, each with its own strengths and weaknesses. Some of the most popular container runtime environments include:
- Docker – The original container runtime environment and the most widely used, Docker provides a complete set of tools for building, deploying, and managing containers.
- rkt (Rocket) – An alternative to Docker, rkt was designed to be more secure and customizable. It uses a different approach to container management, focusing on simplicity and composability.
- CRI-O – An open-source container runtime for Kubernetes, CRI-O is designed to be more lightweight and efficient than Docker. It focuses on providing a minimal runtime for containers, with a smaller attack surface and lower overhead.
- containerd – A lightweight container runtime designed to be used as a library, containerd provides a low-level API for managing containers. It is commonly used as the underlying runtime for other container orchestration platforms, such as Docker and Kubernetes.
- LXD – A system container manager for Linux, LXD is designed to provide a lightweight and fast way to run multiple isolated Linux systems on a single host.

Each of these container runtime environments has its own unique features and trade-offs, so the choice of which to use will depend on the specific needs of the organisation and its applications.